The Brompton Mixture is a relatively new approach to narcotic analgesic therapy, especially in the United States. The mixture consists of an elixir containing a narcotic (usually morphine), cocaine, ethyl alcohol, cherry syrup and water. A phenothiazine is usually given with the mixture. Early studies have suggested that the Brompton Mixture offers significant advantages over conventional narcotic therapy in that (1) pain is significantly reduced by relatively low doses of oral narcotics, (2) significant tolerance does not appear to develop even after years of treatment and (3) adequate levels of analgesic can be induced without serious side effects. However, there have been no controlled studies designed to determine whether the Brompton Mixture is significantly more effective than narcotic alone, and if so, which component of the mixture is responsible for the enhanced effectiveness. Two other significant aspects of the study are (1) its use of a series of psychological tests to assess mood changes in concert with pain relief, and (2) its use of a computer based decision tree to modify medication doses, allowing a double-blinded state to be maintained during the study.